Just a quick observation.
Ice thickness 5", a local BOW that is larger has 8" of ice.

This is a groundwater pond. Temps were taken at the deepest part of the pond, which is currently at 15', at noon today.

1' depth - 35.8*
5' depth - 41.0*
10' depth - 46.0*

I used an indoor/outdoor thermometer that has a 11' lead. I checked the temp on the outdoor portion against my wireless outdoor thermometer, and they read the same. Pond is currently 4' below full pool. There is an aerator set at 5' below water surface, approx. 60-70 Yds away

Could the higher temps (as compared to Dwight's readings) be caused by the groundwater movement into the pond?

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).